What you should have done is left the carpet in situ. Then you should have drilled holes all along one of the outside walls of the room, threaded rope through it and used your van to power stretch the carpet back onto the grippers.
We cleaned a 100% wool carpet today and used too much hot water. The whole carpet shrunk about 1ft all around the room.The customer was not at home so we lifted the carpet out into the garden and tried to stretch it back using a garden rake which we broke.The carpet was all rippled and badly distorted when we fitted it back.Any advise.